Valve opening/closing timing control device

Abstract

The valve opening/closing timing control device includes: the driving rotating body; the driven rotating body; an advancing chamber and a retarding chamber formed by partitioning a fluid pressure chamber between the driving and driven rotating bodies; and a phase control unit supplying pressurized fluid to the advancing or retarding chamber via an advancing channel or a retarding channel penetrating through the driven rotating body. In the driven rotating body, an outer circumferential member and an inner circumferential member are formed integrally/coaxially with each other. The advancing and retarding channel form a predetermined angle. Between every pair of an advancing channel and a retarding channel, a groove portion is formed in one of an inner circumferential surface of the outer circumferential member and an outer circumferential surface of the inner circumferential member, and an elongated protruding portion is formed on the other, at a position that corresponds to the groove portion.

The invention claimed is: 
     
       1. A valve opening/closing timing control device, comprising:
 a driving rotating body that rotates in synchronization with a crankshaft of an internal combustion engine; 
 a driven rotating body that is located on an inner circumference side of the driving rotating body coaxially with a rotational axis of the driving rotating body so as to be relatively rotatable, and that rotates in synchronization with a camshaft for opening/closing a valve of the internal combustion engine; 
 a fluid pressure chamber that is formed between the driving rotating body and the driven rotating body; 
 an advancing chamber and a retarding chamber that are formed by partitioning the fluid pressure chamber with a partitioning portion that is provided on an outer circumference side of the driven rotating body, and at least one advancing channel and at least one retarding channel that are formed to penetrate through the driven rotating body in a radial direction of the driven rotating body; and 
 a phase control unit for controlling a rotation phase of the driven rotating body relative to the driving rotating body by supplying a pressurized fluid to the advancing chamber or the retarding chamber via the advancing channel or the retarding channel, 
 wherein the driven rotating body has: a cylindrical outer circumferential member that is provided with the partitioning portion; and a cylindrical inner circumferential member that is located on an inside of the outer circumferential member in the radial direction, and the outer circumferential member and the inner circumferential member are formed integrally with and coaxially with each other, 
 the advancing channel and the retarding channel are located such that a predetermined angle is formed by a center line of the advancing channel in a longitudinal direction of the advancing channel and a center line of the retarding channel in a longitudinal direction of the retarding channel, and 
 between every pair of an advancing channel and a retarding channel, a groove portion is formed in one of an inner circumferential surface of the outer circumferential member and an outer circumferential surface of the inner circumferential member, and an elongated protruding portion is formed on the other of the inner circumferential surface of the outer circumferential member and the outer circumferential surface of the inner circumferential member at a position that corresponds to the groove portion. 
 
     
     
       2. The valve opening/closing timing control device according to  claim 1 ,
 wherein the advancing channel and the retarding channel are located at different positions along a rotation direction of the driven rotating body, and 
 the groove portion and the elongated protruding portion are provided to extend in a direction along the rotational axis. 
 
     
     
       3. The valve opening/closing timing control device according to  claim 1 ,
 wherein the advancing channel and the retarding channel that are adjacent to each other are located at different positions along the rotational axis, and 
 the groove portion and the elongated protruding portion are provided to extend along a rotation direction of the driven rotating body. 
 
     
     
       4. The valve opening/closing timing control device according to  claim 2 ,
 wherein the groove portion is formed in the outer circumferential surface of the inner circumferential member, and a protruding portion is formed on the outer circumferential surface of the inner circumferential member, the protruding portion making one end portion of the groove portion more protruding than a remaining portion, and 
 an outer circumferential portion of the inner circumferential member is enveloped in the outer circumferential member using insert casting. 
 
     
     
       5. The valve opening/closing timing control device according to  claim 1 ,
 wherein the groove portion is formed by forge-processing by which pressure is applied to the outer circumferential member or the inner circumferential member in a direction along the rotational axis. 
 
     
     
       6. The valve opening/closing timing control device according to  claim 1 ,
 wherein the advancing channel and the retarding channel penetrate through a bottom surface of the groove portion formed in the inner circumferential member. 
 
     
     
       7. The valve opening/closing timing control device according to  claim 1 ,
 wherein the inner circumferential member is formed with an iron-based material. 
 
     
     
       8. The valve opening/closing timing control device according to  claim 1 ,
 wherein the outer circumferential member is formed with a material that is lighter in weight than iron-based materials. 
 
     
     
       9. A valve opening/closing timing control device, comprising:
 a driving rotating body that rotates in synchronization with a crankshaft of an internal combustion engine; 
 a driven rotating body that is located on an inner circumference side of the driving rotating body coaxially with a rotational axis of the driving rotating body so as to be relatively rotatable, and that rotates in synchronization with a camshaft for opening/closing a valve of the internal combustion engine; 
 a fluid pressure chamber that is formed between the driving rotating body and the driven rotating body; 
 an advancing chamber and a retarding chamber that are formed by partitioning the fluid pressure chamber with a partitioning portion that is provided on an outer circumference side of the driven rotating body, and at least one advancing channel and at least one retarding channel that are formed to penetrate through the driven rotating body in a radial direction of the driven rotating body; and 
 a phase control unit for controlling a rotation phase of the driven rotating body relative to the driving rotating body by supplying a pressurized fluid to the advancing chamber or the retarding chamber via the advancing channel or the retarding channel, 
 wherein the driven rotating body has: a cylindrical outer circumferential member that is provided with the partitioning portion; and a cylindrical inner circumferential member that is located on an inside of the outer circumferential member in the radial direction, and the outer circumferential member and the inner circumferential member are formed integrally with and coaxially with each other, 
 a columnar portion that has a height that allows a front end surface thereof to be exposed from an outer circumferential surface of the outer circumferential member is formed integrally with the inner circumferential member so as to extend from an outer circumferential surface of the inner circumferential member, an outer circumferential portion of the inner circumferential member is enveloped in the outer circumferential member using insert casting, and thus the outer circumferential member and the inner circumferential member are joined together, and 
 the advancing channel and the retarding channel extend to a surface that is flush with the front end surface of the columnar portion, and penetrate through the inner circumferential member. 
 
     
     
       10. A valve opening/closing timing control device, comprising:
 a driving rotating body that rotates in synchronization with a crankshaft of an internal combustion engine; 
 a driven rotating body that is located on an inner circumference side of the driving rotating body coaxially with a rotational axis of the driving rotating body so as to be relatively rotatable, and that rotates in synchronization with a camshaft for opening/closing a valve of the internal combustion engine; 
 a fluid pressure chamber that is formed between the driving rotating body and the driven rotating body; 
 an advancing chamber and a retarding chamber that are formed by partitioning the fluid pressure chamber with a partitioning portion that is provided on an outer circumference side of the driven rotating body, and at least one advancing channel and at least one retarding channel that are formed to penetrate through the driven rotating body in a radial direction of the driven rotating body; and 
 a phase control unit for controlling a rotation phase of the driven rotating body relative to the driving rotating body by supplying a pressurized fluid to the advancing chamber or the retarding chamber via the advancing channel or the retarding channel, 
 wherein the driven rotating body has: a cylindrical outer circumferential member that is provided with the partitioning portion; and a cylindrical inner circumferential member that is located on an inside of the outer circumferential member in the radial direction, the outer circumferential member and the inner circumferential member are formed integrally with and coaxially with each other, a through hole that penetrates through the inner circumferential member in a radial direction of the driven rotating body is formed in the inner circumferential member, the outer circumferential member and the inner circumferential member are joined together by, using insert casting, enveloping an outer circumferential portion of the inner circumferential member in the outer circumferential member such that a portion of the outer circumferential member becomes embedded in the through hole, and the advancing channel and the retarding channel penetrate through the portion of the outer circumferential member that is filled in the through hole.